The Half-Astrophysicist Blog

Supernova in M82

I have been busy and not had as much time to do any astrophotography recently. Fortunately, I had some good luck and timing yesterday.

Wednesday morning, I woke up to news of a supernova in M82. Fortunately, I saw this before I went to work. I was scheduled to work with some students at Tohono O’odham Commuity College in Sells last night and thought I might get a chance to try to catch the supernova from there. The college site is nice and dark so it was worth a shot throwing my equipment in the car. Fortune also smiled with clear skies when I got out there.

I was using my Canon 60D, EF 75-300mm zoom lens and iOptron Skytracker, my usual setup. Although there are people with larger, better setups out there that will no doubt take more spectacular pics, I can at least purse the record for the person who imaged the supernova with the smallest setup!

I took some pics of M82 and the nearby galaxy M81 a few weeks ago before the supernova. Here is one of those pics. I took this one on Christmas Eve and believe I used my 250mm lens so the scale is a little different.

11543164176_f1aedfb94c_oOkay, now here is the one from last night. The two lines point to the new little point of light that is the supernova (I did not crop the pics the same and they were taken with slightly different lenses so the scale is different). Click the images for larger versions.

12103271733_0d5c3c8542_oHopefully you can see the new little dot of light. It’s position matches up with the position of the supernova.

This supernova is interesting for many reasons. First, M82 is undergoing a rapid burst of star formation due to a recent pass by the nearby galaxy M81 (also seen in the pic). Increased rates of star formation lead to higher rates of supernova. Second, M82 is a relatively nearby galaxy (only 12 million light years away or so) which means we can study it in greater detail than more distant supernova.

Finally, this is a type 1a supernova. Type 1a supernova form when a white dwarf star sucks matter off a nearby companion star. White dwarfs have a maximum mass about 1.4 times the mass of our Sun. If you add more matter than that, you get a huge explosion which destroys the star. This white dwarf suffered that fate leading to the supernova we are now observing.

Since type 1a supernova always happen when the mass hits 1.4 times that of our Sun, they are always about the same brightness. If you know the brightness of an object, you can figure out its distance. Type 1a supernova are very bright and can be seen in distant galaxies and are very important for astronomers to determine the distance to other galaxies. The more we can study nearby ones, the better we understand them and the better we can measure the distances to other galaxies. Therefore, astronomers are training lots of scopes on this supernova right now!

Oh, I got so excited about the pics, I should mention that we saw it visually as well. We were using a 6″ Celestron Nexstar SE and could see a little bright spot in the galaxy right where the supernova is. I am always nervous showing objects like this to people as you sometimes get the disappointed “Is that it?” reaction. The students last night, however, were happy to be able to see it and I didn’t have to deal with that common reaction. So I can tell you it is visible with a 6″ or larger scope…wouldn’t surprise me if people spot it with even smaller scopes.

This supernova looks like it was discovered before peak brightness. It will probably get brighter for another week or two before starting to fade. How much brighter is an open question and hard to predict. We don’t know how long it took after the explosion for us to discover the supernova (several pre-discovery images have already turned up) and there may be intervening dust that dims the supernova. Worst case scenario, it will not get worse for a week or two. Best case scenario, it brightens another couple of magnitudes.

My sympathies to the northerners who have to brave the cold to see it…I was out in just a sweatshirt last night!

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January 23, 2014 Posted by | Astrophotography, Galaxies, Supernova | , | 1 Comment

Saguaro Star Trails

Just a quick star trails shot I did last night…well, if you can call 43 minutes quick. This is 103 exposures of 25 seconds each put together with StarStax to create this image from Saguaro National Park east in Tucson. I used my Canon 60D and Tokina 11-16mm f/2.8 lens at 11mm and f/2.8. I wanted the saguaros in the foreground. I didn’t center on polaris since the farther west I pointed, the more the lights of Tucson interfered. Hope you like it.

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December 27, 2013 Posted by | Astrophotography, Star Trails | , | Leave a comment

Hunting the Horsehead

When I was in grade school and first getting into astronomy, the Horsehead Nebula was one of the most intriguing objects in the sky. It was on the top of the list of things I wanted to see. When I got my first little 60mm refracting telescope, I spend hours scanning Orion looking for it, never finding it…and of course never listening to people who told me (correctly) that it was WAY beyond the reach of a 60mm telescope!

Earlier this week, I had the pleasure of going out on a shoot with an excellent astrophotographer, Sean Parker (if you don’t know his stuff, go look now!) He wanted to try out the iOptron Skytracker I had and he had borrowed a Canon 5D Mk III and a 70-200 f/2.8 lens so we had some great equipment to play with.

He took several shots of Orion using different exposures and got the Horsehead! I was thrilled to see this, but since this is a lifelong obsession of mine, I wasn’t quite satisfied. I wanted to get a pic of it with my camera and my lens (even though neither my camera or lens are as good as what he was using). So Christmas Eve, I went out with my Canon 60D and EF-s 55-250mm zoom lens. Since my lens can’t operate at f/2.8, I had to use longer exposure and higher ISO, but am pleased to report that yes, I got everything (although I didn’t take and blend multiple exposures…I have a way to go before I get as good as Sean!)

IMG_8953The Orion Nebula is at the bottom right with the Running Man just to its upper left. In the far upper left of the image is the Flame Nebula. Now look closely in the pinkish haze to the lower right of the Flame and you will see a VERY small dark horsehead shape. I got the nebula! Yes, I nerd out over that.

Although this is the shot I really wanted, I of course took some others as well. I will start off with the Andromeda Galaxy.IMG_8943Next I will go for the Pleiades. Notice the gas around it. We used to think (and some astronomers still mistakenly will say) that this is the cloud of gas and dust in which these young stars were born. However, the IRAS (Infrared Astronomy Satellite) mission showed that the stars were plowing through this gas at a high rate of speed. IRAS showed the shockwaves as the stars interact with the gas. Given the very different velocities of the stars and gas, this is almost certainly not where they were born.

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The constellation of Auriga has a wealth of star clusters as it is in the heart of the winter Milky Way. A wide shot can capture three of them at once. M37 is the bottom of the three, M36 is the middle and M38 is at the top. The Messier objects aren’t really in any particular order around the sky! These are all open clusters. The stars were born at the same time from the same cloud of gas and dust, but they are not gravitationally bound to each other so the stars will scatter around the galaxy as time goes on. They are not quite close enough together to get all three in the field of view of my 8×42 binoculars at one time…I can get either the two and the third will be just outside the field of view!

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I will make one more stop here. This pari of galaxies is M81 and M82 about 10 million light years away in Ursa Major. M81 (on the right) is a spiral galaxy much like our own Milky Way. M82 on the left is an irregular galaxy (sometimes nicknamed the Cigar Galaxy) that recently passed nearby M81. The gravitational interaction between the galaxies led to a burst of star formation in M82. M82 is called (appropriately) a starburst galaxy.

IMG_8977Winter in Tucson is a great time to observe. The nights have not been too cold and the skies have been clear. I hope to get out and do some very wide field stuff in the next few days and hope that it is clear this weekend as we have our great ISS passes coming up.

December 26, 2013 Posted by | Astrophotography, Galaxies, iOptron Skytracker, Uncategorized | 2 Comments

Comet Lovejoy and the Hercules Cluster

I got behind posting here, but last Sunday morning I went out to get Comet Lovejoy as it was passing a little over 5 degrees from the Hercules Globular cluster, also known as M13. It would have been better Saturday morning, but I got back from a trip late Friday night and getting up early Saturday just didn’t happen.

The problem Sunday morning was the Moon. The Moon was approaching full and lit up the sky when I got to Saguaro National Park east. I couldn’t see Lovejoy with the naked eye, but found it with binoculars. I took a few pics while waiting for the Moon to set. Once the Moon set, there was a very brief window before morning twilight started brightening the sky. Fortunately, I was ready to make the most of the 20 minutes or so I had.

Here is Comet Lovejoy in the lower right of the image and the fuzzy blob of M13 in the upper left.

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Next I zoomed in for a closer view of Lovejoy.

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Lovejoy still has a very nice tail. I could see the comet as a fuzzy blob naked eye once the Moon set, but it is not quite as bright as it was a couple of weeks ago.  Finally, as the sky began to gradually brighten, I found a nice saguaro and did a much wider shot with the comet.

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The Moon is entering the morning sky and will make Comet Lovejoy much less impressive, but it should still be in reach of binoculars. The comet if forecast to slowly fade to a magnitude of about 6.0 by the end of the month when the Moon will finally get out of the way. You would need really dark skies to catch it with the naked eye although it should still be all right in binoculars. Due to the Moon, I probably won’t try for it again for a couple of weeks. However, I hope to use some of the slower time around the holidays next week to try some photography in the evening!

December 17, 2013 Posted by | Astrophotography, Comet Lovejoy, Comets | , | Leave a comment

Lovejoy Rising

I have posted lots of pics of Comet Lovejoy and managed to get up early enough this morning and brave the chilly Tucson (below freezing…don’t judge northerners!) temps to take some shots.

Saguaro National Park east is about a 10 minute drive from where I live. I wanted some pics with some nice foreground objects so I hiked into the park a little bit to get to the first batch of big saguaros. I got several wide shots with a 35mm lens. I used a feature on my Skytracker that will track at only half the rate the stars move across the sky. I did this to split the difference between the land and sky, keeping both of them reasonably in focus with minimal blurring during the 20-30 second exposures I was using.

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Of course I felt the need to put on the longer (250mm) zoom lens and try a two minute shot of the comet. The tail is developing nicely and covers several degrees of the sky.

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Comet Lovejoy was visible to the naked eye and it is definitely brighter than M13, probably a little brighter than 5th magnitude. Easy and nice binocular target, naked eye under dark skies. For finder chart, Heavens Above is a good place. Just set it to the time you want to observe.

I should note that Lovejoy is moving farther into the northern sky. For much of the continental U.S., it can be seen after sunset and before sunrise, although it is much higher in the sky and easier to see before sunrise. The farther north you are, the easier it is to see after sunset (although Mike Weasner got it after sunset from Oracle, just north of Tucson a few nights ago so anything Tucson or north is fair game for sure!)

I am enjoying this comet, but could the next one please be a good evening object?

December 7, 2013 Posted by | Astrophotography, Comet Lovejoy, Comets | | 3 Comments

Star Trails Over Kitt Peak

I have always wanted to try a star trails picture. A couple of weeks ago, I had an evening at Kitt Peak. The Moon was waxing gibbous and very bright and lit up the domes very nicely. I was with a group over by the 0.9 meter telescope so I set up my camera outside, programmed it to take 30 second exposures for a few hours, and went about my work.

I ended up with 162  262 pictures by the time we were getting ready to go. I made some adjustments in Lightroom to tame the bright sky and then imported them into a free program called StarStax. StarStax will add the individual images automatically and create the star trails picture for you. There are some options you can adjust, but it’s pretty automated. Here is the result.

11216894843_961f75c538_oOverall I am pretty pleased with the first attempt. I can spot a couple of flaws to clean up (and I would like to figure out where they came from, but I might have to look closely at 162 pictures to find the bloody things!) You can see the north star in its tight dance around the celestial pole and many other stars making nice trails. The lights of Tucsonare off to the right.

I have some old pics I used to make time lapses. I might go back and put together a few more of these from those old pics.

December 5, 2013 Posted by | Astrophotography, Kitt Peak, Star Trails | , | 1 Comment

Air Glow Over Kitt Peak

Another shot from my night on Kitt Peak a few days ago. This is a wide shot taken from the Visitor’s Center.

IMG_2520You can see the iconic McMath-Pierce Solar Telescope in the background and the sky glow from Tucson on the left. However, if you look on the right side of the image, you will notice a faint green glow and possibly even fainter red if you look close. This is a real phenomena called air glow. Due to air glow, the sky is never completely dark. Airglow occurs all over the sky but is usually more pronounced close to the horizon since you are looking through a thicker layer of atmosphere.

There are several sources of air glow. During the day, atoms in the upper atmosphere are ionized by sunlight. When the ionized atoms and electrons recombine, they give off light…and oxygen can give off green light in the process. Cosmic rays striking the upper atmosphere contribute to air glow as well. Finally, oxygen and nitrogen can react with hydroxyl ions in the upper atmosphere and give off light through a process called chemiluminescence.

Air glow is not visible during the day as it far too faint. Even at night, you need to be in a very dark site to capture it. Thursday night was the first time I have captured this elusive phenomena.

December 3, 2013 Posted by | air glow, Astrophotography, Kitt Peak | , | Leave a comment

Green Flashes From Chile

Sitting around Kitt Peak today, I had some extra time and went back and took care of something that has been on my to do list. I photographed a great sunset from Cerro Tololo Inter-American Observatory back in March. I wanted to animate all the pics so you could see the progression of green flashes. I finally did that today and am pleased with the results.

This animation is roughly real time so they move fairly quickly. You can watch the green flashes (yes, plural) break off the Sun, move away and disappear. Look at the last green flash…do you see other colors as it vanishes? I recommend checking this one out full screen!

November 30, 2013 Posted by | Astrophotography, Atmospheric Physics, Green Flash, Sunset | Leave a comment

An Open Letter From Comet Lovejoy

Dear Earthlings,

I see you have been really excited about Comet ISON. There was a lot of hype about it being the “Comet of the Century”, “Brighter than the full Moon” and a “Once in a lifetime experience”.  I am happy my comet brother seems to have survived his close pass to the Sun. I wish ISON nothing but the best.

However, I can’t help but feeling a little ignored over here. I know I was only discovered on September 7th so maybe I kind of snuck up on you. I was originally only forecast to reach 8th magnitude according to Universe Today so maybe people thought you would need a big telescope to see me.

But hey, I have been working hard to put on a good show for you and I don’t feel like anyone is paying much attention to me. I have brightened up a lot more than expected and can be seen with the naked eye from a moderately dark site. I bet most city dwellers could find me with binoculars without too much difficulty. Heck, you can even photograph me with off the shelf cameras. Look at this shot from this morning taken with a Canon 60D and Ef-s 55-250mm zoom lens. Okay, he used an iOptron Skytracker to take a longer exposure, but I think I am looking pretty good here!

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Come on, look at that tail! If you look close, I think you can tell there are two tails!

I am about at my brightest and best right now. I am going to start slowly fading as I get farther away from Earth but I think you have a few more weeks to take a shot at seeing me. I am hanging below the handle of the Big Dipper right now, one of the easiest things to find in the sky. Here is a finder chart from Heavens Above to help you out. Change the date and time if you need to because I move quick!

Okay, I am a morning Comet so you will have to get that strong cup of coffee when you come to see me. It will be worth it. The Moon is a slender crescent now and not too bright so it doesn’t interfere with seeing me. The Moon will be new December 2nd and move into the evening sky leaving me in a pristine, dark morning sky, the perfect time to check me out!

So, do we have a date? I would love to meet you all before I leave. I mean “Love” is right there in my name! I won’t be back for about 8,000 years or so and it would break my heart not to meet you.

Sincerely,

Comet Lovejoy

November 29, 2013 Posted by | Astrophotography, Comet Lovejoy, Observing | 3 Comments

Comet ISON Brightens Rapidly

It has been a few days since I got out to image Comet ISON but I finally made it out this morning…trying to beat the Moon which will shortly be returning to the morning sky. Much to my surprise, ISON has brightened up quite a bit since Sunday morning. It was easy in 8×42 binoculars and its nucleus is much brighter. Again I set up my Canon 60D with a EF-s 55-250mm zoom lens. The following pic is at 250mm, f/5.6, ISO 5000 and a 90 second exposure.

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Not hard to see the bright nucleus and the tail is developing. If you look to the left of the comet, you might notice a faint blue smudge. I believe that is galaxy NGC 4697. I have seen other people post pics from earlier today on the internet (most using telescopes) and I got my smudge in the same place they got a galaxy. I am happy I got it using my less extravagant equipment. Visually, it was pretty easy in 8×42 binoculars and looking good in 20x80s.

I turned my attention to Comet Lovejoy, still riding high in Leo and a very nice site. Pretty much the same settings for this shot as the previous one.

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I looked briefly for Comet Encke again but didn’t find it this time…I didn’t spend too much time on it as it is getting pretty low in they sky. However, the fourth I haven’t nabbed yet, Comet LINEAR, was passing close to Arcturus so I went for it. It proved to be very difficult. I barely got it and was debating whether to post this photo at all, but what the hey, see if you can spot the VERY faint blue smudge toward the top of the image above Arcturus (clicking to look at a larger version might help). The comet is slightly left of directly above Arcturus (the brightest star) near the top of the photo. I might go back and add an arrow pointing to it later.

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Like I said, not very impressive at all, but I went for it to add a notch to the proverbial comet belt.

The weather may get dicey in Tucson over the weekend and the Moon will soon return to the morning sky, but I will try to get out every couple of days to observe.

On another note, I was on Kitt Peak last night. Lots of photos that I have to put together into time lapses and star trail photos. Busy few days so it may take a while to get to it, but I am looking forward to trying some new things!

 

November 14, 2013 Posted by | Astrophotography, Comet ISON, Comet Lovejoy | , , | Leave a comment